The diagram below shows a disaccharide called lactose. The carbon atoms are numbered. You are not expected to have seen this structure before. Lactose is a reducing sugar found in milk. It is made from a reaction between the two monosaccharides glucose and galactose.

a. Suggest two functions that lactose could have.

b. What is the name given to the reaction referred to above that results in the formation of lactose?

c. Identify the bond labelled X in the diagram.

d. Draw diagrams to show the structures of separate molecules of glucose and galactose.

e. Using the information in the diagram, is the alpha or beta form of glucose used to make lactose? Explain your answer.

f. Like lactose, sucrose is a disaccharide. If you were given a solution of lactose and a solution of sucrose, state briefly how you could distinguish between them.

Transcribed Image Text:

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